users = ['A','B','admin','C','D']
# users = []
if users:
    for u in users:
        if u == 'admin':
            print('hello:' + u)
        else:
            print('Hi')
else:
    print('need some users')

names = ['A', 'B', 'C', 'D', 'E'] 
exist_name = ['B', 'E']
for _name in names:
    if _name in exist_name:
        print('in')   
    else:
        print('out')    